# $Id: Pg.pm,v 1.73 2003/11/14 20:38:44 rlippan Exp $
#
# Copyright (c) 1997,1998,1999,2000 Edmund Mergl
# Copyright (c) 2002 Jeffrey W. Baker
# Copyright (c) 2002,2003 PostgreSQL Global Development Group
# Portions Copyright (c) 1994,1995,1996,1997 Tim Bunce
#
# You may distribute under the terms of either the GNU General Public
# License or the Artistic License, as specified in the Perl README file.
use 5.006001;
$DBD::Pg::VERSION = '1.31_9';
{
package DBD::Pg;
use DBI ();
use DynaLoader ();
use Exporter ();
@ISA = qw(DynaLoader Exporter);
%EXPORT_TAGS = (
pg_types => [ qw(
PG_BOOL PG_BYTEA PG_CHAR PG_INT8 PG_INT2 PG_INT4 PG_TEXT PG_OID
PG_FLOAT4 PG_FLOAT8 PG_ABSTIME PG_RELTIME PG_TINTERVAL PG_BPCHAR
PG_VARCHAR PG_DATE PG_TIME PG_DATETIME PG_TIMESPAN PG_TIMESTAMP
)]);
Exporter::export_ok_tags('pg_types');
require_version DBI 1.35;
bootstrap DBD::Pg $VERSION;
$err = 0; # holds error code for DBI::err
$errstr = ""; # holds error string for DBI::errstr
$drh = undef; # holds driver handle once initialized
sub driver{
return $drh if $drh;
my($class, $attr) = @_;
$class .= "::dr";
# not a 'my' since we use it above to prevent multiple drivers
$drh = DBI::_new_drh($class, {
'Name' => 'Pg',
'Version' => $VERSION,
'Err' => \$DBD::Pg::err,
'Errstr' => \$DBD::Pg::errstr,
'Attribution' => 'PostgreSQL DBD by Edmund Mergl',
});
$drh;
}
## Used by both the dr and db packages
sub _pg_server_version {
my $dbh = shift;
return $dbh->{private_dbdpg}->{server_version} if defined $dbh->{private_dbdpg}->{server_version};
my ($version) = $dbh->selectrow_array("SELECT version();");
$dbh->{private_dbdpg}->{server_version} = ($version =~ /^PostgreSQL ([\d\.]+)/) ? $1 : 0;
return $dbh->{private_dbdpg}->{server_version};
}
## Is the second version greater than or equal to the first?
# Returns:
# 0 if first version is greater
# 1 if they are equal
# 2 if second version is greater
sub _pg_check_version($$) {
## Check each section from left to right
my @uno = split (/\./ => $_[0]);
my @dos = split (/\./ => $_[1]);
for (my $i=0; defined $uno[$i] or defined $dos[$i]; $i++) {
$uno[$i] = 0 if ! defined $uno[$i];
$dos[$i] = 0 if ! defined $dos[$i];
return 2 if $uno[$i] < $dos[$i];
return 0 if $uno[$i] > $dos[$i];
}
return 1; ## versions are equal
}
## Version 7.3 and up uses schemas, so add a "pg_catalog." to system tables
sub _pg_use_catalog {
my $dbh = shift;
return $dbh->{pg_use_catalog} if defined $dbh->{pg_use_catalog};
my $version = DBD::Pg::_pg_server_version($dbh);
$dbh->{pg_use_catalog} = DBD::Pg::_pg_check_version(7.3, $version) ? "pg_catalog." : "";
return $dbh->{pg_use_catalog};
}
1;
}
{ package DBD::Pg::dr; # ====== DRIVER ======
use strict;
sub data_sources {
my $drh = shift;
my $dbh = DBD::Pg::dr::connect($drh, 'dbname=template1') or return undef;
$dbh->{AutoCommit} = 1;
my $CATALOG = DBD::Pg::_pg_use_catalog($dbh);
my $sth = $dbh->prepare("SELECT datname FROM ${CATALOG}pg_database ORDER BY datname");
$sth->execute or return undef;
my (@sources, @datname);
while (@datname = $sth->fetchrow_array) {
push @sources, "dbi:Pg:dbname=$datname[0]";
}
$sth->finish;
$dbh->disconnect;
return @sources;
}
sub connect {
my($drh, $dbname, $user, $auth)= @_;
# create a 'blank' dbh
my $Name = $dbname;
if ($dbname =~ m#dbname\s*=\s*\"([^\"]+)\"# or $dbname =~ m#dbname\s*=\s*([^;]+)#) {
$Name = $1;
}
$user = "" unless defined($user);
$auth = "" unless defined($auth);
$user = $ENV{DBI_USER} if $user eq "";
$auth = $ENV{DBI_PASS} if $auth eq "";
$user = "" unless defined($user);
$auth = "" unless defined($auth);
my($dbh) = DBI::_new_dbh($drh, {
'Name' => $Name,
'User' => $user, 'CURRENT_USER' => $user,
});
# Connect to the database..
DBD::Pg::db::_login($dbh, $dbname, $user, $auth) or return undef;
$dbh;
}
}
{ package DBD::Pg::db; # ====== DATABASE ======
use strict;
use Carp ();
sub prepare {
my($dbh, $statement, @attribs)= @_;
# create a 'blank' sth
my $sth = DBI::_new_sth($dbh, {
'Statement' => $statement,
});
DBD::Pg::st::_prepare($sth, $statement, @attribs) or return undef;
$sth;
}
sub ping {
my($dbh) = @_;
local $SIG{__WARN__} = sub { } if $dbh->{PrintError};
local $dbh->{RaiseError} = 0 if $dbh->{RaiseError};
my $ret = DBD::Pg::db::_ping($dbh);
return $ret;
}
sub pg_type_info {
my($dbh,$pg_type) = @_;
local $SIG{__WARN__} = sub { } if $dbh->{PrintError};
local $dbh->{RaiseError} = 0 if $dbh->{RaiseError};
my $ret = DBD::Pg::db::_pg_type_info($pg_type);
return $ret;
}
# Column expected in statement handle returned.
# table_cat, table_schem, table_name, column_name, data_type, type_name,
# column_size, buffer_length, DECIMAL_DIGITS, NUM_PREC_RADIX, NULLABLE,
# REMARKS, COLUMN_DEF, SQL_DATA_TYPE, SQL_DATETIME_SUB, CHAR_OCTET_LENGTH,
# ORDINAL_POSITION, IS_NULLABLE
# The result set is ordered by TABLE_SCHEM, TABLE_NAME and ORDINAL_POSITION.
sub column_info {
my $dbh = shift;
my ($catalog, $schema, $table, $column) = @_;
my $CATALOG = DBD::Pg::_pg_use_catalog($dbh);
my $version = DBD::Pg::_pg_server_version($dbh);
my @search;
## If the schema or table has an underscore or a %, use a LIKE comparison
if (defined $schema and length $schema and DBD::Pg::_pg_check_version(7.3, $version)) {
push @search, "n.nspname " . ($schema =~ /[_%]/ ? "LIKE " : "= ") .
$dbh->quote($schema);
}
if (defined $table and length $table) {
push @search, "c.relname " . ($table =~ /[_%]/ ? "LIKE " : "= ") .
$dbh->quote($table);
}
if (defined $column and length $column) {
push @search, "a.attname " . ($column =~ /[_%]/ ? "LIKE " : "= ") .
$dbh->quote($column);
}
my $whereclause = join "\n\t\t\t\tAND ", "", @search;
my $showschema = DBD::Pg::_pg_check_version(7.3, $version) ?
"n.nspname" : "NULL::text";
my $schemajoin = DBD::Pg::_pg_check_version(7.3, $version) ?
"JOIN pg_catalog.pg_namespace n ON (n.oid = c.relnamespace)" : "";
# Create a join to get the correct description (for Pg < 7.2 or >= 7.2)
my $pg_description_join = DBD::Pg::_pg_check_version(7.2, $version)
? "LEFT JOIN ${CATALOG}pg_description d ON (a.attnum = d.objsubid)\n".
"\t\t\t\tLEFT JOIN ${CATALOG}pg_class dc ON (dc.oid = d.objoid )"
: "LEFT JOIN ${CATALOG}pg_description d ON (a.oid = d.objoid )";
my $col_info_sql = qq!
SELECT
NULL::text AS "TABLE_CAT"
, $showschema AS "TABLE_SCHEM"
, c.relname AS "TABLE_NAME"
, a.attname AS "COLUMN_NAME"
, a.atttypid AS "DATA_TYPE"
, ${CATALOG}format_type(a.atttypid, NULL) AS "TYPE_NAME"
, a.attlen AS "COLUMN_SIZE"
, NULL::text AS "BUFFER_LENGTH"
, NULL::text AS "DECIMAL_DIGITS"
, NULL::text AS "NUM_PREC_RADIX"
, CASE a.attnotnull WHEN 't' THEN 0 ELSE 1 END AS "NULLABLE"
, d.description AS "REMARKS"
, af.adsrc AS "COLUMN_DEF"
, NULL::text AS "SQL_DATA_TYPE"
, NULL::text AS "SQL_DATETIME_SUB"
, NULL::text AS "CHAR_OCTET_LENGTH"
, a.attnum AS "ORDINAL_POSITION"
, CASE a.attnotnull WHEN 't' THEN 'NO' ELSE 'YES' END AS "IS_NULLABLE"
, ${CATALOG}format_type(a.atttypid, a.atttypmod) AS "pg_type"
, ${CATALOG}format_type(a.atttypid, NULL) AS "pg_type_only"
, a.atttypmod AS "pg_atttypmod"
FROM
${CATALOG}pg_type t
JOIN ${CATALOG}pg_attribute a ON (t.oid = a.atttypid)
JOIN ${CATALOG}pg_class c ON (a.attrelid = c.oid)
LEFT JOIN ${CATALOG}pg_attrdef af ON (a.attnum = af.adnum AND a.attrelid = af.adrelid)
$schemajoin
$pg_description_join
WHERE
a.attnum >= 0
AND c.relkind IN ('r','v')
$whereclause
ORDER BY "TABLE_SCHEM", "TABLE_NAME", "ORDINAL_POSITION"
!;
my $data = $dbh->selectall_arrayref($col_info_sql) or return undef;
# To turn the data back into a statement handle, we need
# to fetch the data as an array of arrays, and also have a
# a matching array of all the column names
my %col_map = (qw/
TABLE_CAT 0
TABLE_SCHEM 1
TABLE_NAME 2
COLUMN_NAME 3
DATA_TYPE 4
TYPE_NAME 5
COLUMN_SIZE 6
BUFFER_LENGTH 7
DECIMAL_DIGITS 8
NUM_PREC_RADIX 9
NULLABLE 10
REMARKS 11
COLUMN_DEF 12
SQL_DATA_TYPE 13
SQL_DATETIME_SUB 14
CHAR_OCTET_LENGTH 15
ORDINAL_POSITION 16
IS_NULLABLE 17
pg_type 18
pg_type_only 19
pg_atttypmod 20
/);
my $constraint_query = DBD::Pg::_pg_check_version(7.3, $version)
? "SELECT consrc FROM pg_catalog.pg_constraint WHERE contype = 'c' AND conname = ?"
: "SELECT rcsrc FROM pg_relcheck WHERE rcname = ?";
my $constraint_sth = $dbh->prepare($constraint_query);
for my $row (@$data) {
$row->[$col_map{COLUMN_SIZE}] =
_calc_col_size($row->[$col_map{pg_atttypmod}],$row->[$col_map{COLUMN_SIZE}]);
# Replace the Pg type with the SQL_ type
my $w = $row->[$col_map{DATA_TYPE}];
$row->[$col_map{DATA_TYPE}] = DBD::Pg::db::pg_type_info($dbh,$row->[$col_map{DATA_TYPE}]);
$w = $row->[$col_map{DATA_TYPE}];
pop @$row;
# Add pg_constraint
$constraint_sth->execute("$row->[$col_map{TABLE_NAME}]_$row->[$col_map{COLUMN_NAME}]");
$col_map{pg_constraint} = 20;
($row->[$col_map{pg_constraint}]) = $constraint_sth->fetchrow_array;
}
# get rid of atttypmod that we no longer need
delete $col_map{pg_atttypmod};
# Since we've processed the data in Perl, we have to jump through a hoop
# To turn it back into a statement handle
#
my $sth = _prepare_from_data(
'column_info',
$data,
[ sort { $col_map{$a} <=> $col_map{$b} } keys %col_map]);
}
sub _prepare_from_data {
my ($statement, $data, $names, %attr) = @_;
my $sponge = DBI->connect("dbi:Sponge:","","",{ RaiseError => 1 });
my $sth = $sponge->prepare($statement, { rows=>$data, NAME=>$names, %attr });
return $sth;
}
sub primary_key_info {
my $dbh = shift;
my ($catalog, $schema, $table) = @_;
my @attrs = @_;
my $CATALOG = DBD::Pg::_pg_use_catalog($dbh);
# TABLE_CAT:, TABLE_SCHEM:, TABLE_NAME:, COLUMN_NAME:, KEY_SEQ:
# , PK_NAME:
my @wh = (); my @dat = (); # Used to hold data for the attributes.
my $version = DBD::Pg::_pg_server_version($dbh);
my @flds = qw/catname n.nspname bc.relname/;
for my $idx (0 .. $#attrs) {
next if $flds[$idx] eq 'catname'; # Skip catalog
next if $flds[$idx] eq 'n.nspname' and ! DBD::Pg::_pg_check_version(7.3, $version);
if(defined $attrs[$idx] and length $attrs[$idx]) {
push( @dat, $attrs[$idx] );
push( @wh, qq{$flds[$idx] = ? } );
}
}
my $wh = '';
$wh = join( " AND ", '', @wh ) if (@wh);
# Base primary key selection query borrowed from phpPgAdmin.
my $showschema = DBD::Pg::_pg_check_version(7.3, $version) ?
"n.nspname" : "NULL::text";
my $schemajoin = DBD::Pg::_pg_check_version(7.3, $version) ?
"LEFT JOIN pg_catalog.pg_namespace n ON (n.oid = bc.relnamespace)" : "";
my $indexjoin = DBD::Pg::_pg_check_version(7.4, $version) ?
"i.indexprs IS NULL" : "i.indproc = '0'::oid";
my $pri_key_sql = qq{
SELECT
NULL::text AS "TABLE_CAT"
, $showschema AS "TABLE_SCHEM"
, bc.relname AS "TABLE_NAME"
, a.attname AS "COLUMN_NAME"
, a.attnum AS "KEY_SEQ"
, ic.relname AS "PK_NAME"
FROM
${CATALOG}pg_index i
, ${CATALOG}pg_attribute a
, ${CATALOG}pg_class ic
, ${CATALOG}pg_class bc
$schemajoin
WHERE
i.indrelid = bc.oid
AND i.indexrelid = ic.oid
AND
(
i.indkey[0] = a.attnum
OR
i.indkey[1] = a.attnum
OR
i.indkey[2] = a.attnum
OR
i.indkey[3] = a.attnum
OR
i.indkey[4] = a.attnum
OR
i.indkey[5] = a.attnum
OR
i.indkey[6] = a.attnum
OR
i.indkey[7] = a.attnum
OR
i.indkey[8] = a.attnum
OR
i.indkey[9] = a.attnum
OR
i.indkey[10] = a.attnum
OR
i.indkey[11] = a.attnum
OR
i.indkey[12] = a.attnum
)
AND a.attrelid = bc.oid
AND $indexjoin
AND i.indisprimary = 't'
$wh
ORDER BY 2, 3, 5
};
my $sth = $dbh->prepare( $pri_key_sql ) or return undef;
$sth->execute(@dat);
return $sth;
}
sub foreign_key_info {
# todo: verify schema work as expected
# add code to handle multiple-column keys correctly
# return something nicer for pre-7.3?
# try to clean up SQL, perl code
# create a test script?
my $dbh = shift;
my ($pk_catalog, $pk_schema, $pk_table,
$fk_catalog, $fk_schema, $fk_table) = @_;
# this query doesn't work for Postgres before 7.3
my $version = DBD::Pg::_pg_server_version($dbh);
return undef unless DBD::Pg::_pg_check_version(7.3, $version);
# Used to hold data for the attributes.
my @dat = ();
# SQL to find primary/unique keys of a table
my $pkey_sql = qq{
SELECT
NULL::text AS PKTABLE_CAT,
pknam.nspname AS PKTABLE_SCHEM,
pkc.relname AS PKTABLE_NAME,
pka.attname AS PKCOLUMN_NAME,
NULL::text AS FKTABLE_CAT,
NULL::text AS FKTABLE_SCHEM,
NULL::text AS FKTABLE_NAME,
NULL::text AS FKCOLUMN_NAME,
pkcon.conkey[1] AS KEY_SEQ,
CASE
WHEN pkcon.confupdtype = 'c' THEN 0
WHEN pkcon.confupdtype = 'r' THEN 1
WHEN pkcon.confupdtype = 'n' THEN 2
WHEN pkcon.confupdtype = 'a' THEN 3
WHEN pkcon.confupdtype = 'd' THEN 4
END AS UPDATE_RULE,
CASE
WHEN pkcon.confdeltype = 'c' THEN 0
WHEN pkcon.confdeltype = 'r' THEN 1
WHEN pkcon.confdeltype = 'n' THEN 2
WHEN pkcon.confdeltype = 'a' THEN 3
WHEN pkcon.confdeltype = 'd' THEN 4
END AS DELETE_RULE,
NULL::text AS FK_NAME,
pkcon.conname AS PK_NAME,
CASE
WHEN pkcon.condeferrable = 'f' THEN 7
WHEN pkcon.condeferred = 't' THEN 6
WHEN pkcon.condeferred = 'f' THEN 5
END AS DEFERRABILITY,
CASE
WHEN pkcon.contype = 'p' THEN 'PRIMARY'
WHEN pkcon.contype = 'u' THEN 'UNIQUE'
END AS UNIQUE_OR_PRIMARY
FROM
pg_constraint AS pkcon
JOIN
pg_class pkc ON pkc.oid=pkcon.conrelid
JOIN
pg_namespace pknam ON pkcon.connamespace=pknam.oid
JOIN
pg_attribute pka ON pka.attnum=pkcon.conkey[1] AND pka.attrelid=pkc.oid
};
# SQL to find foreign keys of a table
my $fkey_sql = qq{
SELECT
NULL::text AS PKTABLE_CAT,
pknam.nspname AS PKTABLE_SCHEM,
pkc.relname AS PKTABLE_NAME,
pka.attname AS PKCOLUMN_NAME,
NULL::text AS FKTABLE_CAT,
fknam.nspname AS FKTABLE_SCHEM,
fkc.relname AS FKTABLE_NAME,
fka.attname AS FKCOLUMN_NAME,
fkcon.conkey[1] AS KEY_SEQ,
CASE
WHEN fkcon.confupdtype = 'c' THEN 0
WHEN fkcon.confupdtype = 'r' THEN 1
WHEN fkcon.confupdtype = 'n' THEN 2
WHEN fkcon.confupdtype = 'a' THEN 3
WHEN fkcon.confupdtype = 'd' THEN 4
END AS UPDATE_RULE,
CASE
WHEN fkcon.confdeltype = 'c' THEN 0
WHEN fkcon.confdeltype = 'r' THEN 1
WHEN fkcon.confdeltype = 'n' THEN 2
WHEN fkcon.confdeltype = 'a' THEN 3
WHEN fkcon.confdeltype = 'd' THEN 4
END AS DELETE_RULE,
fkcon.conname AS FK_NAME,
pkcon.conname AS PK_NAME,
CASE
WHEN fkcon.condeferrable = 'f' THEN 7
WHEN fkcon.condeferred = 't' THEN 6
WHEN fkcon.condeferred = 'f' THEN 5
END AS DEFERRABILITY,
CASE
WHEN pkcon.contype = 'p' THEN 'PRIMARY'
WHEN pkcon.contype = 'u' THEN 'UNIQUE'
END AS UNIQUE_OR_PRIMARY
FROM
pg_constraint AS fkcon
JOIN
pg_constraint AS pkcon ON fkcon.confrelid=pkcon.conrelid
AND fkcon.confkey=pkcon.conkey
JOIN
pg_class fkc ON fkc.oid=fkcon.conrelid
JOIN
pg_class pkc ON pkc.oid=fkcon.confrelid
JOIN
pg_namespace pknam ON pkcon.connamespace=pknam.oid
JOIN
pg_namespace fknam ON fkcon.connamespace=fknam.oid
JOIN
pg_attribute fka ON fka.attnum=fkcon.conkey[1] AND fka.attrelid=fkc.oid
JOIN
pg_attribute pka ON pka.attnum=pkcon.conkey[1] AND pka.attrelid=pkc.oid
};
# if schema are provided, use this SQL
my $pk_schema_sql = " AND pknam.nspname = ? ";
my $fk_schema_sql = " AND fknam.nspname = ? ";
my $key_sql;
# if $fk_table: generate SQL stub, which will be same
# whether or not $pk_table supplied
if ($fk_table)
{
$key_sql = $fkey_sql . qq{
WHERE
fkc.relname = ?
};
push @dat, $fk_table;
if ($fk_schema)
{
$key_sql .= $fk_schema_sql;
push @dat,$fk_schema;
}
}
# if $fk_table and $pk_table: (defined by DBI, not SQL/CLI)
# return foreign key of $fk_table that refers to $pk_table
# (if any)
if ($pk_table and $fk_table)
{
$key_sql .= qq{
AND
pkc.relname = ?
};
push @dat, $pk_table;
if ($pk_schema)
{
$key_sql .= $pk_schema_sql;
push @dat,$pk_schema;
}
}
# if $fk_table but no $pk_table:
# return all foreign keys of $fk_table, and all
# primary keys of tables to which $fk_table refers
if (!$pk_table and $fk_table)
{
# find primary/unique keys referenced by $fk_table
# (this one is a little tricky)
$key_sql .= ' UNION ' . $pkey_sql . qq{
WHERE
pkcon.conname IN
(
SELECT
pkcon.conname
FROM
pg_constraint AS fkcon
JOIN
pg_constraint AS pkcon ON
fkcon.confrelid=pkcon.conrelid AND fkcon.confkey=pkcon.conkey
JOIN
pg_class fkc ON fkc.oid=fkcon.conrelid
WHERE
fkc.relname = ?
)
};
push @dat, $fk_table;
if ($fk_schema)
{
$key_sql .= $pk_schema_sql;
push @dat,$fk_schema;
}
}
# if $pk_table but no $fk_table:
# return primary key of $pk_table and all foreign keys
# that reference $pk_table
# question: what about unique keys?
# (DBI and SQL/CLI both state to omit unique keys)
if ($pk_table and !$fk_table)
{
# find primary key (only!) of $pk_table
$key_sql = $pkey_sql . qq{
WHERE
pkc.relname = ?
AND
pkcon.contype = 'p'
};
@dat = ($pk_table);
if ($pk_schema)
{
$key_sql .= $pk_schema_sql;
push @dat,$pk_schema;
}
# find all foreign keys that reference $pk_table
$key_sql .= 'UNION ' . $fkey_sql . qq{
WHERE
pkc.relname = ?
AND
pkcon.contype = 'p'
};
push @dat, $pk_table;
if ($pk_schema)
{
$key_sql .= $fk_schema_sql;
push @dat,$pk_schema;
}
}
return undef unless $key_sql;
my $sth = $dbh->prepare( $key_sql ) or
return undef;
$sth->execute(@dat);
return $sth;
}
sub table_info { # DBI spec: TABLE_CAT, TABLE_SCHEM, TABLE_NAME, TABLE_TYPE, REMARKS
my $dbh = shift;
my ($catalog, $schema, $table, $type) = @_;
my $tbl_sql = ();
my $version = DBD::Pg::_pg_server_version($dbh);
my $CATALOG = DBD::Pg::_pg_use_catalog($dbh);
if ( # Rule 19a
(defined $catalog and $catalog eq '%')
and (defined $schema and $schema eq '')
and (defined $table and $table eq '')
) {
$tbl_sql = q{
SELECT
NULL::text AS "TABLE_CAT"
, NULL::text AS "TABLE_SCHEM"
, NULL::text AS "TABLE_NAME"
, NULL::text AS "TABLE_TYPE"
, NULL::text AS "REMARKS"
};
}
elsif (# Rule 19b
(defined $catalog and $catalog eq '')
and (defined $schema and $schema eq '%')
and (defined $table and $table eq '')
) {
$tbl_sql = DBD::Pg::_pg_check_version(7.3, $version) ?
q{SELECT
NULL::text AS "TABLE_CAT"
, n.nspname AS "TABLE_SCHEM"
, NULL::text AS "TABLE_NAME"
, NULL::text AS "TABLE_TYPE"
, CASE WHEN n.nspname ~ '^pg_' THEN 'system schema' ELSE 'owned by ' || pg_get_userbyid(n.nspowner) END AS "REMARKS"
FROM pg_catalog.pg_namespace n
ORDER BY "TABLE_SCHEM"
} :
q{SELECT
NULL::text AS "TABLE_CAT"
, NULL::text AS "TABLE_SCHEM"
, NULL::text AS "TABLE_NAME"
, NULL::text AS "TABLE_TYPE"
, NULL::text AS "REMARKS"
};
}
elsif (# Rule 19c
(defined $catalog and $catalog eq '')
and (defined $schema and $schema eq '')
and (defined $table and $table eq '')
and (defined $type and $type eq '%')
) {
$tbl_sql = q{
SELECT
NULL::text AS "TABLE_CAT"
, NULL::text AS "TABLE_SCHEM"
, NULL::text AS "TABLE_NAME"
, 'TABLE' AS "TABLE_TYPE"
, 'relkind: r' AS "REMARKS"
UNION
SELECT
NULL::text AS "TABLE_CAT"
, NULL::text AS "TABLE_SCHEM"
, NULL::text AS "TABLE_NAME"
, 'VIEW' AS "TABLE_TYPE"
, 'relkind: v' AS "REMARKS"
};
}
else {
# Default SQL
my $showschema = "NULL::text";
my $schemajoin = "";
my $has_objsubid = "";
if (DBD::Pg::_pg_check_version(7.3, $version)) {
$showschema = "n.nspname";
$schemajoin = "LEFT JOIN pg_catalog.pg_namespace n ON (n.oid = c.relnamespace)";
$has_objsubid = "AND d.objsubid = 0";
}
my @search;
## If the schema or table has an underscore or a %, use a LIKE comparison
if (defined $schema and length $schema and DBD::Pg::_pg_check_version(7.3, $version)) {
push @search, "n.nspname " . ($schema =~ /[_%]/ ? "LIKE " : "= ") . $dbh->quote($schema);
}
if (defined $table and length $table) {
push @search, "c.relname " . ($table =~ /[_%]/ ? "LIKE " : "= ") . $dbh->quote($table);
}
## All we can see is "table" or "view". Default is both
my $typesearch = "IN ('r','v')";
if (defined $type and length $type) {
if ($type =~ /\btable\b/i and $type !~ /\bview\b/i) {
$typesearch = "= 'r'";
}
elsif ($type =~ /\bview\b/i and $type !~ /\btable\b/i) {
$typesearch = "= 'v'";
}
}
push @search, "c.relkind $typesearch";
my $whereclause = join "\n\t\t\t\t\t AND " => @search;
my $schemacase = DBD::Pg::_pg_check_version(7.3, $version) ? "n.nspname" : "c.relname";
$tbl_sql = qq{
SELECT NULL::text AS "TABLE_CAT"
, $showschema AS "TABLE_SCHEM"
, c.relname AS "TABLE_NAME"
, CASE
WHEN c.relkind = 'v' THEN
CASE WHEN $schemacase ~ '^pg_' THEN 'SYSTEM VIEW' ELSE 'VIEW' END
ELSE
CASE WHEN $schemacase ~ '^pg_' THEN 'SYSTEM TABLE' ELSE 'TABLE' END
END AS "TABLE_TYPE"
, d.description AS "REMARKS"
FROM ${CATALOG}pg_class AS c
LEFT JOIN ${CATALOG}pg_description AS d
ON (c.relfilenode = d.objoid $has_objsubid)
$schemajoin
WHERE $whereclause
ORDER BY "TABLE_TYPE", "TABLE_CAT", "TABLE_SCHEM", "TABLE_NAME"
};
}
my $sth = $dbh->prepare( $tbl_sql ) or return undef;
$sth->execute();
return $sth;
}
sub tables {
my ($dbh, @args) = @_;
my $sth = $dbh->table_info(@args) or return;
my $tables = $sth->fetchall_arrayref() or return;
my $version = DBD::Pg::_pg_server_version($dbh);
my @tables = map { DBD::Pg::_pg_check_version(7.3, $version) ?
"$_->[1].$_->[2]" : $_->[2] } @$tables;
return @tables;
}
sub table_attributes {
my ($dbh, $table) = @_;
my $CATALOG = DBD::Pg::_pg_use_catalog($dbh);
my $sth = $dbh->column_info(undef,undef,$table);
my %convert = (
COLUMN_NAME => 'NAME',
DATA_TYPE => 'TYPE',
COLUMN_SIZE => 'SIZE',
NULLABLE => 'NOTNULL',
REMARKS => 'REMARKS',
COLUMN_DEF => 'DEFAULT',
pg_constraint => 'CONSTRAINT',
);
my $attrs = $sth->fetchall_arrayref(\%convert);
foreach my $row (@$attrs) {
# switch the column names
for my $name (keys %$row) {
$row->{ $convert{$name} } = $row->{$name};
# The REMARKS column is an exception because the name is the same
delete $row->{$name} unless ($name eq 'REMARKS');
}
# Moved check outside of loop as it was inverting the NOTNULL value for
# attribute.
# NOTNULL inverts the sense of NULLABLE
$row->{NOTNULL} = ($row->{NOTNULL} ? 0 : 1);
my @pri_keys = ();
@pri_keys = $dbh->primary_key( $CATALOG, undef, $table );
$row->{PRIMARY_KEY} = scalar(grep { /^$row->{NAME}$/i } @pri_keys) ? 1 : 0;
}
return $attrs;
}
sub _calc_col_size {
my $mod = shift;
my $size = shift;
if ((defined $size) and ($size > 0)) {
return $size;
} elsif ($mod > 0xffff) {
my $prec = ($mod & 0xffff) - 4;
$mod >>= 16;
my $dig = $mod;
return "$prec,$dig";
} elsif ($mod >= 4) {
return $mod - 4;
} # else {
# $rtn = $mod;
# $rtn = undef;
# }
return;
}
sub type_info_all {
my ($dbh) = @_;
my $names = {
TYPE_NAME => 0,
DATA_TYPE => 1,
COLUMN_SIZE => 2, # was PRECISION originally
LITERAL_PREFIX => 3,
LITERAL_SUFFIX => 4,
CREATE_PARAMS => 5,
NULLABLE => 6,
CASE_SENSITIVE => 7,
SEARCHABLE => 8,
UNSIGNED_ATTRIBUTE=> 9,
FIXED_PREC_SCALE => 10, # was MONEY originally
AUTO_UNIQUE_VALUE => 11, # was AUTO_INCREMENT originally
LOCAL_TYPE_NAME => 12,
MINIMUM_SCALE => 13,
MAXIMUM_SCALE => 14,
NUM_PREC_RADIX => 15,
};
# typname |typlen|typprtlen| SQL92
# --------------+------+---------+ -------
# bool | 1| 1| BOOLEAN
# text | -1| -1| like VARCHAR, but automatic storage allocation
# bpchar | -1| -1| CHARACTER(n) bp=blank padded
# varchar | -1| -1| VARCHAR(n)
# int2 | 2| 5| SMALLINT
# int4 | 4| 10| INTEGER
# int8 | 8| 20| /
# money | 4| 24| /
# float4 | 4| 12| FLOAT(p) for p<7=float4, for p<16=float8
# float8 | 8| 24| REAL
# abstime | 4| 20| /
# reltime | 4| 20| /
# tinterval | 12| 47| /
# date | 4| 10| /
# time | 8| 16| /
# datetime | 8| 47| /
# timespan | 12| 47| INTERVAL
# timestamp | 4| 19| TIMESTAMP
# --------------+------+---------+
# DBI type definitions / PostgreSQL definitions # type needs to be DBI-specific (not pg_type)
#
# SQL_ALL_TYPES 0
# SQL_CHAR 1 1042 bpchar
# SQL_NUMERIC 2 700 float4
# SQL_DECIMAL 3 700 float4
# SQL_INTEGER 4 23 int4
# SQL_SMALLINT 5 21 int2
# SQL_FLOAT 6 700 float4
# SQL_REAL 7 701 float8
# SQL_DOUBLE 8 20 int8
# SQL_DATE 9 1082 date
# SQL_TIME 10 1083 time
# SQL_TIMESTAMP 11 1296 timestamp
# SQL_VARCHAR 12 1043 varchar
my $ti = [
$names,
# name type prec prefix suffix create params null case se unsign mon incr local min max
#
[ 'bytea', -2, 4096, '\'', '\'', undef, 1, '1', 3, undef, '0', '0', 'BYTEA', undef, undef, undef ],
[ 'bool', 0, 1, '\'', '\'', undef, 1, '0', 2, undef, '0', '0', 'BOOLEAN', undef, undef, undef ],
[ 'int8', 8, 20, undef, undef, undef, 1, '0', 2, '0', '0', '0', 'LONGINT', undef, undef, undef ],
[ 'int2', 5, 5, undef, undef, undef, 1, '0', 2, '0', '0', '0', 'SMALLINT', undef, undef, undef ],
[ 'int4', 4, 10, undef, undef, undef, 1, '0', 2, '0', '0', '0', 'INTEGER', undef, undef, undef ],
[ 'text', 12, 4096, '\'', '\'', undef, 1, '1', 3, undef, '0', '0', 'TEXT', undef, undef, undef ],
[ 'float4', 6, 12, undef, undef, 'precision', 1, '0', 2, '0', '0', '0', 'FLOAT', undef, undef, undef ],
[ 'float8', 7, 24, undef, undef, 'precision', 1, '0', 2, '0', '0', '0', 'REAL', undef, undef, undef ],
[ 'abstime', 10, 20, '\'', '\'', undef, 1, '0', 2, undef, '0', '0', 'ABSTIME', undef, undef, undef ],
[ 'reltime', 10, 20, '\'', '\'', undef, 1, '0', 2, undef, '0', '0', 'RELTIME', undef, undef, undef ],
[ 'tinterval', 11, 47, '\'', '\'', undef, 1, '0', 2, undef, '0', '0', 'TINTERVAL', undef, undef, undef ],
[ 'money', 0, 24, undef, undef, undef, 1, '0', 2, undef, '1', '0', 'MONEY', undef, undef, undef ],
[ 'bpchar', 1, 4096, '\'', '\'', 'max length', 1, '1', 3, undef, '0', '0', 'CHARACTER', undef, undef, undef ],
[ 'bpchar', 12, 4096, '\'', '\'', 'max length', 1, '1', 3, undef, '0', '0', 'CHARACTER', undef, undef, undef ],
[ 'varchar', 12, 4096, '\'', '\'', 'max length', 1, '1', 3, undef, '0', '0', 'VARCHAR', undef, undef, undef ],
[ 'date', 9, 10, '\'', '\'', undef, 1, '0', 2, undef, '0', '0', 'DATE', undef, undef, undef ],
[ 'time', 10, 16, '\'', '\'', undef, 1, '0', 2, undef, '0', '0', 'TIME', undef, undef, undef ],
[ 'datetime', 11, 47, '\'', '\'', undef, 1, '0', 2, undef, '0', '0', 'DATETIME', undef, undef, undef ],
[ 'timespan', 11, 47, '\'', '\'', undef, 1, '0', 2, undef, '0', '0', 'INTERVAL', undef, undef, undef ],
[ 'timestamp', 10, 19, '\'', '\'', undef, 1, '0', 2, undef, '0', '0', 'TIMESTAMP', undef, undef, undef ]
#
# intentionally omitted: char, all geometric types, all array types
];
return $ti;
}
# Characters that need to be escaped by quote().
my %esc = (
"'" => '\\047', # '\\' . sprintf("%03o", ord("'")), # ISO SQL 2
'\\' => '\\134', # '\\' . sprintf("%03o", ord("\\")),
);
# Set up lookup for SQL types we don't want to escape.
my %no_escape = map { $_ => 1 }
DBI::SQL_INTEGER, DBI::SQL_SMALLINT, DBI::SQL_DECIMAL,
DBI::SQL_FLOAT, DBI::SQL_REAL, DBI::SQL_DOUBLE, DBI::SQL_NUMERIC;
sub get_info {
my ($dbh,$type) = @_;
return undef unless defined $type and length $type;
my $version = DBD::Pg::_pg_server_version($dbh);
my %type = (
## Basic information:
6 => ["SQL_DRIVER_NAME", 'DBD/Pg.pm', ],
17 => ["SQL_DBMS_NAME", 'PostgreSQL' ],
18 => ["SQL_DBMS_VERSION", 'ODBCVERSION' ],
29 => ["SQL_IDENTIFIER_QUOTE_CHAR", '\"' ],
41 => ["SQL_CATALOG_NAME_SEPARATOR", '' ],
47 => ["SQL_USER_NAME", $dbh->{CURRENT_USER} ],
## Size limits
30 => ["SQL_MAX_COLUMN_NAME_LEN", 'NAMEDATALEN' ],
32 => ["SQL_MAX_SCHEMA_NAME_LEN", 'NAMEDATALEN' ],
34 => ["SQL_MAX_CATALOG_NAME_LEN", 0 ],
35 => ["SQL_MAX_TABLE_NAME_LEN", 'NAMEDATALEN' ],
97 => ["SQL_MAX_COLUMNS_IN_GROUP_BY", 0 ],
98 => ["SQL_MAX_COLUMNS_IN_INDEX", 0 ],
99 => ["SQL_MAX_COLUMNS_IN_ORDER_BY", 0 ],
100 => ["SQL_MAX_COLUMNS_IN_SELECT", 0 ],
101 => ["SQL_MAX_COLUMNS_IN_TABLE", 0 ],
102 => ["SQL_MAX_INDEX_SIZE", 0 ],
104 => ["SQL_MAX_ROW_SIZE", 0 ],
105 => ["SQL_MAX_STATEMENT_LEN", 0 ],
106 => ["SQL_MAX_TABLES_IN_SELECT", 0 ],
107 => ["SQL_MAX_USER_NAME_LEN", 'NAMEDATALEN' ],
108 => ["SQL_MAX_STATEMENT_LEN", 0 ],
109 => ["SQL_MAX_STATEMENT_LEN", 0 ],
105 => ["SQL_MAX_STATEMENT_LEN", 0 ],
105 => ["SQL_MAX_STATEMENT_LEN", 0 ],
112 => ["SQL_MAX_BINARY_LITERAL_LEN", 0 ],
10005 => ["SQL_MAX_IDENTIFIER_LEN", 'NAMEDATALEN' ],
## Catalog support
41 => ["SQL_CATALOG_NAME_SEPARATOR", '' ],
42 => ["SQL_CATALOG_TERM", '' ],
114 => ["SQL_CATALOG_LOCATION", 0 ],
10003 => ["SQL_CATALOG_NAME", 'N' ],
## Domain support
117 => ["SQL_ALTER_DOMAIN", 0 ],
130 => ["SQL_CREATE_DOMAIN", 0 ],
139 => ["SQL_DROP_DOMAIN", 0 ],
## Schema support (7.3 and up)
39 => ["SQL_SCHEMA_TERM", 'schema' ],
91 => ["SQL_SCHEMA_USAGE", 'SCHEMAUSAGE' ],
131 => ["SQL_CREATE_SCHEMA", 'CREATESCHEMA' ],
140 => ["SQL_DROP_SCHEMA", 'DROPSCHEMA' ],
## Various
2 => ["SQL_DATA_SOURCE_NAME", 'SOURCENAME' ],
7 => ["SQL_DRIVER_VER", 'DBDVERSION' ],
13 => ["SQL_SERVER_NAME", $dbh->{Name} ],
14 => ["SQL_SEARCH_PATTERN_ESCAPE", '\\' ],
22 => ["SQL_CONCAT_NULL_BEHAVIOR", 0 ], ## SQL_CB_NULL
28 => ["SQL_IDENTIFIER_CASE", 4 ], ## SQL_IC_MIXED
29 => ["SQL_IDENTIFIER_QUOTE_CHAR", '\"' ],
40 => ["SQL_PROCEDURE_TERM", 'Function' ],
45 => ["SQL_TABLE_TERM", 'Table' ],
46 => ["SQL_TXN_CAPABLE", 4 ], ## SQL_TC_ALL
87 => ["SQL_COLUMN_ALIAS", 'Y' ],
90 => ["SQL_ORDER_BY_COLUMNS_IN_SELECT", 'N' ],
93 => ["SQL_QUOTED_IDENTIFIER_CASE", 3 ], ## SQL_IC_SENSITIVE
113 => ["SQL_LIKE_ESCAPE_CLAUSE", 'Y' ],
127 => ["SQL_CREATE_ASSERTION", 0 ],
136 => ["SQL_DROP_ASSERTION", 0 ],
);
## Put both numbers and names into a hash
my %t;
for (keys %type) {
$t{$_} = $type{$_}->[1];
$t{$type{$_}->[0]} = $type{$_}->[1];
}
return undef unless exists $t{$type};
my $ans = $t{$type};
if ($ans eq 'NAMEDATALEN') {
return DBD::Pg::_pg_check_version(7.3, $version) ? 63 : 31;
}
elsif ($ans eq 'ODBCVERSION') {
return sprintf "%02d.%02d.%1d%1d%1d%1d", split (/\./, "$version.0.0.0.0.0.0");
}
elsif ($ans eq 'DBDVERSION') {
my $simpleversion = $DBD::Pg::VERSION;
$simpleversion =~ s/_/./g;
return sprintf "%02d.%02d.%1d%1d%1d%1d", split (/\./, "$simpleversion.0.0.0.0.0.0");
}
elsif ($ans eq 'SOURCENAME') {
return "dbi:Pg:dbname=$dbh->{Name}";
}
elsif ($ans eq 'SCHEMAUSAGE') {
return 0 if ! DBD::Pg::_pg_check_version(7.3, $version);
my %bitmask = (
SQL_SU_DML_STATEMENT => 1,
SQL_SU_PROCEDURE_INVOCATION => 2,
SQL_SU_TABLE_DEFINITION => 4,
SQL_SU_INDEX_DEFINITION => 8,
SQL_SU_PRIVILEGE_DEFINITION => 16,
);
return 31; ## all of the above
}
elsif ($ans eq 'CREATESCHEMA') {
return 0 if ! DBD::Pg::_pg_check_version(7.3, $version);
my %bitmask = (
SQL_CS_CREATE_SCHEMA => 1,
SQL_CS_AUTHORIZATION => 2,
SQL_CS_DEFAULT_CHARACTER_SET => 4
);
return $bitmask{SQL_CS_CREATE_SCHEMA} + $bitmask{SQL_CS_AUTHORIZATION};
}
elsif ($ans eq 'DROPSCHEMA') {
return 0 if ! DBD::Pg::_pg_check_version(7.3, $version);
my %bitmask = (
SQL_DS_DROP_SCHEMA => 1,
SQL_DS_RESTRICT => 2,
SQL_DS_CASCADE => 4
);
return 7; ## All of the above
}
return $ans;
} # end of get_info
} # end of package DBD::Pg::db
{ package DBD::Pg::st; # ====== STATEMENT ======
# all done in XS
}
1;
__END__
=head1 NAME
DBD::Pg - PostgreSQL database driver for the DBI module
=head1 SYNOPSIS
use DBI;
$dbh = DBI->connect("dbi:Pg:dbname=$dbname", "", "");
# for some advanced uses you may need PostgreSQL type values:
use DBD::Pg qw(:pg_types);
# See the DBI module documentation for full details
=head1 DESCRIPTION
DBD::Pg is a Perl module which works with the DBI module to provide access to
PostgreSQL databases.
=head1 MODULE DOCUMENTATION
This documentation describes driver specific behavior and restrictions. It is
not supposed to be used as the only reference for the user. In any case
consult the DBI documentation first!
=head1 THE DBI CLASS
=head2 DBI Class Methods
=over 4
=item B<connect>
To connect to a database with a minimum of parameters, use the following
syntax:
$dbh = DBI->connect("dbi:Pg:dbname=$dbname", "", "");
This connects to the database $dbname at localhost without any user
authentication. This is sufficient for the defaults of PostgreSQL.
The following connect statement shows all possible parameters:
$dbh = DBI->connect("dbi:Pg:dbname=$dbname;host=$host;port=$port;" .
"options=$options;tty=$tty", "$username", "$password");
If a parameter is undefined PostgreSQL first looks for specific environment
variables and then it uses hard coded defaults:
parameter environment variable hard coded default
--------------------------------------------------
dbname PGDATABASE current userid
host PGHOST localhost
port PGPORT 5432
options PGOPTIONS ""
tty PGTTY ""
username PGUSER current userid
password PGPASSWORD ""
If a host is specified, the postmaster on this host needs to be started with
the C<-i> option (TCP/IP sockets).
The options parameter specifies runtime options for the Postgres
backend. Common usage is to increase the number of buffers with the C<-B>
option. Also important is the C<-F> option, which disables automatic fsync()
call after each transaction. For further details please refer to the
L<postgres>.
For authentication with username and password appropriate entries have to be
made in pg_hba.conf. Please refer to the L<pg_hba.conf> and the L<pg_passwd>
for the different types of authentication. Note that for these two parameters
DBI distinguishes between empty and undefined. If these parameters are
undefined DBI substitutes the values of the environment variables DBI_USER and
DBI_PASS if present.
=item B<available_drivers>
@driver_names = DBI->available_drivers;
Implemented by DBI, no driver-specific impact.
=item B<data_sources>
@data_sources = DBI->data_sources('Pg');
The driver supports this method. Note that the necessary database connection to
the database template1 will be done on the localhost without any
user-authentication. Other preferences can only be set with the environment
variables PGHOST, DBI_USER and DBI_PASS.
=item B<trace>
DBI->trace($trace_level, $trace_file)
Implemented by DBI, no driver-specific impact.
=back
=head2 DBI Dynamic Attributes
See Common Methods.
=head1 METHODS COMMON TO ALL HANDLES
=over 4
=item B<err>
$rv = $h->err;
Supported by the driver as proposed by DBI. For the connect method it returns
PQstatus. In all other cases it returns PQresultStatus of the current handle.
=item B<errstr>
$str = $h->errstr;
Supported by the driver as proposed by DBI. It returns the PQerrorMessage
related to the current handle.
=item B<state>
$str = $h->state;
This driver does not (yet) support the state method.
=item B<trace>
$h->trace($trace_level, $trace_filename);
Implemented by DBI, no driver-specific impact.
=item B<trace_msg>
$h->trace_msg($message_text);
Implemented by DBI, no driver-specific impact.
=item B<func>
This driver supports a variety of driver specific functions accessible via the
func interface:
$attrs = $dbh->func($table, 'table_attributes');
The C<table_attributes> function is no longer recommended. Instead,
you can use the more portable C<column_info> and C<primary_key> functions
to access all the same information.
This method returns for the given table a reference to an array of hashes:
NAME attribute name
TYPE attribute type
SIZE attribute size (-1 for variable size)
NULLABLE flag nullable
DEFAULT default value
CONSTRAINT constraint
PRIMARY_KEY flag is_primary_key
REMARKS attribute description
$lobjId = $dbh->func($mode, 'lo_creat');
Creates a new large object and returns the object-id. $mode is a bit-mask
describing different attributes of the new object. Use the following
constants:
$dbh->{pg_INV_WRITE}
$dbh->{pg_INV_READ}
Upon failure it returns undef.
$lobj_fd = $dbh->func($lobjId, $mode, 'lo_open');
Opens an existing large object and returns an object-descriptor for use in
subsequent lo_* calls. For the mode bits see lo_create. Returns undef upon
failure. Note that 0 is a perfectly correct object descriptor!
$nbytes = $dbh->func($lobj_fd, $buf, $len, 'lo_write');
Writes $len bytes of $buf into the large object $lobj_fd. Returns the number
of bytes written and undef upon failure.
$nbytes = $dbh->func($lobj_fd, $buf, $len, 'lo_read');
Reads $len bytes into $buf from large object $lobj_fd. Returns the number of
bytes read and undef upon failure.
$loc = $dbh->func($lobj_fd, $offset, $whence, 'lo_lseek');
Change the current read or write location on the large object
$obj_id. Currently $whence can only be 0 (L_SET). Returns the current location
and undef upon failure.
$loc = $dbh->func($lobj_fd, 'lo_tell');
Returns the current read or write location on the large object $lobj_fd and
undef upon failure.
$lobj_fd = $dbh->func($lobj_fd, 'lo_close');
Closes an existing large object. Returns true upon success and false upon
failure.
$lobj_fd = $dbh->func($lobj_fd, 'lo_unlink');
Deletes an existing large object. Returns true upon success and false upon
failure.
$lobjId = $dbh->func($filename, 'lo_import');
Imports a Unix file as large object and returns the object id of the new
object or undef upon failure.
$ret = $dbh->func($lobjId, $filename, 'lo_export');
Exports a large object into a Unix file. Returns false upon failure, true
otherwise.
$ret = $dbh->func($line, 'putline');
Used together with the SQL-command 'COPY table FROM STDIN' to copy large
amount of data into a table avoiding the overhead of using single
insert commands. The application must explicitly send the two characters "\."
to indicate to the backend that it has finished sending its data.
$ret = $dbh->func($buffer, length, 'getline');
Used together with the SQL-command 'COPY table TO STDOUT' to dump a complete
table.
$ret = $dbh->func('pg_notifies');
Returns either undef or a reference to two-element array [ $table,
$backend_pid ] of asynchronous notifications received.
$fd = $dbh->func('getfd');
Returns fd of the actual connection to server. Can be used with select() and
func('pg_notifies').
=back
=head1 ATTRIBUTES COMMON TO ALL HANDLES
=over 4
=item B<Warn> (boolean, inherited)
Implemented by DBI, no driver-specific impact.
=item B<Active> (boolean, read-only)
Supported by the driver as proposed by DBI. A database handle is active while
it is connected and statement handle is active until it is finished.
=item B<Kids> (integer, read-only)
Implemented by DBI, no driver-specific impact.
=item B<ActiveKids> (integer, read-only)
Implemented by DBI, no driver-specific impact.
=item B<CachedKids> (hash ref)
Implemented by DBI, no driver-specific impact.
=item B<CompatMode> (boolean, inherited)
Not used by this driver.
=item B<InactiveDestroy> (boolean)
Implemented by DBI, no driver-specific impact.
=item B<PrintError> (boolean, inherited)
Implemented by DBI, no driver-specific impact.
=item B<RaiseError> (boolean, inherited)
Implemented by DBI, no driver-specific impact.
=item B<HandleError> (boolean, inherited)
Implemented by DBI, no driver-specific impact.
=item B<ChopBlanks> (boolean, inherited)
Supported by the driver as proposed by DBI. This method is similar to the
SQL-function RTRIM.
=item B<LongReadLen> (integer, inherited)
Implemented by DBI, not used by the driver.
=item B<LongTruncOk> (boolean, inherited)
Implemented by DBI, not used by the driver.
=item B<Taint> (boolean, inherited)
Implemented by DBI, no driver-specific impact.
=item B<private_*>
Implemented by DBI, no driver-specific impact.
=back
=head1 DBI DATABASE HANDLE OBJECTS
=head2 Database Handle Methods
=over 4
=item B<selectrow_array>
@row_ary = $dbh->selectrow_array($statement, \%attr, @bind_values);
Implemented by DBI, no driver-specific impact.
=item B<selectrow_arrayref>
$ary_ref = $dbh->selectrow_arrayref($statement, \%attr, @bind_values);
Implemented by DBI, no driver-specific impact.
=item B<selectrow_hashref>
$hash_ref = $dbh->selectrow_hashref($statement, \%attr, @bind_values);
Implemented by DBI, no driver-specific impact.
=item B<selectall_arrayref>
$ary_ref = $dbh->selectall_arrayref($statement, \%attr, @bind_values);
Implemented by DBI, no driver-specific impact.
=item B<selectall_hashref>
$hash_ref = $dbh->selectall_hashref($statement, $key_field);
Implemented by DBI, no driver-specific impact.
=item B<selectcol_arrayref>
$ary_ref = $dbh->selectcol_arrayref($statement, \%attr, @bind_values);
Implemented by DBI, no driver-specific impact.
=item B<prepare>
$sth = $dbh->prepare($statement, \%attr);
PostgreSQL does not have the concept of preparing a statement. Hence the
prepare method just stores the statement after checking for place-holders. No
information about the statement is available after preparing it.
=item B<prepare_cached>
$sth = $dbh->prepare_cached($statement, \%attr);
Implemented by DBI, no driver-specific impact. This method is not useful for
this driver, because preparing a statement has no database interaction.
=item B<do>
$rv = $dbh->do($statement, \%attr, @bind_values);
Implemented by DBI, no driver-specific impact. See the notes for the execute
method elsewhere in this document.
=item B<commit>
$rc = $dbh->commit;
Supported by the driver as proposed by DBI. See also the notes about
B<Transactions> elsewhere in this document.
=item B<rollback>
$rc = $dbh->rollback;
Supported by the driver as proposed by DBI. See also the notes about
B<Transactions> elsewhere in this document.
=item B<disconnect>
$rc = $dbh->disconnect;
Supported by the driver as proposed by DBI.
=item B<ping>
$rc = $dbh->ping;
This driver supports the ping-method, which can be used to check the validity
of a database-handle. The ping method issues an empty query and checks the
result status.
=item B<column_info>
$sth = $dbh->column_info( $catalog, $schema, $table, $column );
Supported by the driver as proposed by the DBI with the follow exceptions.
These fields are currently always returned with NULL values:
TABLE_CAT
BUFFER_LENGTH
DECIMAL_DIGITS
NUM_PREC_RADIX
SQL_DATA_TYPE
SQL_DATETIME_SUB
CHAR_OCTET_LENGTH
Also, four additional non-standard fields are returned:
pg_type
pg_type_only
pg_attypmod
pg_constraint - holds column constraint definition
=item B<table_info>
$sth = $dbh->table_info( $catalog, $schema, $table, $type );
Supported by the driver as proposed by DBI. This method returns all tables
and views visible to the current user. The $catalog argument is currently
unused. The schema and table arguments will do a 'LIKE' search if a
percent sign (%) or an underscore (_) are detected in the argument.
The $type argument accepts a value of wither "TABLE" or "VIEW"
(using both is the default action).
=item B<foreign_key_info>
$sth = $dbh->foreign_key_info( $pk_catalog, $pk_schema, $pk_table,
$fk_catalog, $fk_schema, $fk_table );
Supported by the driver as proposed by DBI. Unimplemented for Postgres
servers before 7.3 (returns undef). Currently only returns information
about first column of any multiple-column keys.
=item B<tables>
@names = $dbh->tables( $catalog, $schema, $table, $type );
Supported by the driver as proposed by DBI. This method returns all tables and
views which are visible to the current user. If the database is version 7.3
or higher, the name of the schema appears before the table or view name.
=item B<type_info_all>
$type_info_all = $dbh->type_info_all;
Supported by the driver as proposed by DBI. Only for SQL data-types and for
frequently used data-types information is provided. The mapping between the
PostgreSQL typename and the SQL92 data-type (if possible) has been done
according to the following table:
+---------------+------------------------------------+
| typname | SQL92 |
|---------------+------------------------------------|
| bool | BOOL |
| text | / |
| bpchar | CHAR(n) |
| varchar | VARCHAR(n) |
| int2 | SMALLINT |
| int4 | INT |
| int8 | / |
| money | / |
| float4 | FLOAT(p) p<7=float4, p<16=float8 |
| float8 | REAL |
| abstime | / |
| reltime | / |
| tinterval | / |
| date | / |
| time | / |
| datetime | / |
| timespan | TINTERVAL |
| timestamp | TIMESTAMP |
+---------------+------------------------------------+
For further details concerning the PostgreSQL specific data-types please read
the L<pgbuiltin>.
=item B<type_info>
@type_info = $dbh->type_info($data_type);
Implemented by DBI, no driver-specific impact.
=item B<quote>
$sql = $dbh->quote($value, $data_type);
This module implements its own quote method. In addition to the DBI method it
also doubles the backslash, because PostgreSQL treats a backslash as an escape
character.
B<NOTE:> The undocumented (and invalid) support for the C<SQL_BINARY> data
type is officially deprecated. Use C<PG_BYTEA> with C<bind_param()> instead:
$rv = $sth->bind_param($param_num, $bind_value,
{ pg_type => DBD::Pg::PG_BYTEA });
=back
=head2 Database Handle Attributes
=over 4
=item B<AutoCommit> (boolean)
Supported by the driver as proposed by DBI. According to the classification of
DBI, PostgreSQL is a database, in which a transaction must be explicitly
started. Without starting a transaction, every change to the database becomes
immediately permanent. The default of AutoCommit is on, which corresponds to
the default behavior of PostgreSQL. When setting AutoCommit to off, a
transaction will be started and every commit or rollback will automatically
start a new transaction. For details see the notes about B<Transactions>
elsewhere in this document.
=item B<Driver> (handle)
Implemented by DBI, no driver-specific impact.
=item B<Name> (string, read-only)
The default method of DBI is overridden by a driver specific method, which
returns only the database name. Anything else from the connection string is
stripped off. Note, that here the method is read-only in contrast to the DBI
specs.
=item B<RowCacheSize> (integer)
Implemented by DBI, not used by the driver.
=item B<pg_auto_escape> (boolean)
PostgreSQL specific attribute. If true, then quotes and backslashes in all
parameters will be escaped in the following way:
escape quote with a quote (SQL)
escape backslash with a backslash
The default is on. Note, that PostgreSQL also accepts quotes, which are
escaped by a backslash. Any other ASCII character can be used directly in a
string constant.
=item B<pg_enable_utf8> (boolean)
PostgreSQL specific attribute. If true, then the utf8 flag will be
turned for returned character data (if the data is valid utf8). For
details about the utf8 flag, see L<Encode>. This is only relevant under
perl 5.8 and higher.
B<NB>: This attribute is experimental and may be subject to change.
=item B<pg_INV_READ> (integer, read-only)
Constant to be used for the mode in lo_creat and lo_open.
=item B<pg_INV_WRITE> (integer, read-only)
Constant to be used for the mode in lo_creat and lo_open.
=back
=head1 DBI STATEMENT HANDLE OBJECTS
=head2 Statement Handle Methods
=over 4
=item B<bind_param>
$rv = $sth->bind_param($param_num, $bind_value, \%attr);
Supported by the driver as proposed by DBI.
B<NOTE:> The undocumented (and invalid) support for the C<SQL_BINARY>
SQL type is officially deprecated. Use C<PG_BYTEA> instead:
$rv = $sth->bind_param($param_num, $bind_value,
{ pg_type => DBD::Pg::PG_BYTEA });
=item B<bind_param_inout>
Not supported by this driver.
=item B<execute>
$rv = $sth->execute(@bind_values);
Supported by the driver as proposed by DBI. In addition to 'UPDATE', 'DELETE',
'INSERT' statements, for which it returns always the number of affected rows,
the execute method can also be used for 'SELECT ... INTO table' statements.
=item B<fetchrow_arrayref>
$ary_ref = $sth->fetchrow_arrayref;
Supported by the driver as proposed by DBI.
=item B<fetchrow_array>
@ary = $sth->fetchrow_array;
Supported by the driver as proposed by DBI.
=item B<fetchrow_hashref>
$hash_ref = $sth->fetchrow_hashref;
Supported by the driver as proposed by DBI.
=item B<fetchall_arrayref>
$tbl_ary_ref = $sth->fetchall_arrayref;
Implemented by DBI, no driver-specific impact.
=item B<finish>
$rc = $sth->finish;
Supported by the driver as proposed by DBI.
=item B<rows>
$rv = $sth->rows;
Supported by the driver as proposed by DBI. In contrast to many other drivers
the number of rows is available immediately after executing the statement.
=item B<bind_col>
$rc = $sth->bind_col($column_number, \$var_to_bind, \%attr);
Supported by the driver as proposed by DBI.
=item B<bind_columns>
$rc = $sth->bind_columns(\%attr, @list_of_refs_to_vars_to_bind);
Supported by the driver as proposed by DBI.
=item B<dump_results>
$rows = $sth->dump_results($maxlen, $lsep, $fsep, $fh);
Implemented by DBI, no driver-specific impact.
=item B<blob_read>
$blob = $sth->blob_read($id, $offset, $len);
Supported by this driver as proposed by DBI. Implemented by DBI but not
documented, so this method might change.
This method seems to be heavily influenced by the current implementation of
blobs in Oracle. Nevertheless we try to be as compatible as possible. Whereas
Oracle suffers from the limitation that blobs are related to tables and every
table can have only one blob (data-type LONG), PostgreSQL handles its blobs
independent of any table by using so called object identifiers. This explains
why the blob_read method is blessed into the STATEMENT package and not part of
the DATABASE package. Here the field parameter has been used to handle this
object identifier. The offset and len parameter may be set to zero, in which
case the driver fetches the whole blob at once.
Starting with PostgreSQL-6.5 every access to a blob has to be put into a
transaction. This holds even for a read-only access.
See also the PostgreSQL-specific functions concerning blobs which are
available via the func-interface.
For further information and examples about blobs, please read the chapter
about Large Objects in the PostgreSQL Programmer's Guide.
=back
=head2 Statement Handle Attributes
=over 4
=item B<NUM_OF_FIELDS> (integer, read-only)
Implemented by DBI, no driver-specific impact.
=item B<NUM_OF_PARAMS> (integer, read-only)
Implemented by DBI, no driver-specific impact.
=item B<NAME> (array-ref, read-only)
Supported by the driver as proposed by DBI.
=item B<NAME_lc> (array-ref, read-only)
Implemented by DBI, no driver-specific impact.
=item B<NAME_uc> (array-ref, read-only)
Implemented by DBI, no driver-specific impact.
=item B<TYPE> (array-ref, read-only)
Supported by the driver as proposed by DBI
=item B<PRECISION> (array-ref, read-only)
Not supported by the driver.
=item B<SCALE> (array-ref, read-only)
Not supported by the driver.
=item B<NULLABLE> (array-ref, read-only)
Not supported by the driver.
=item B<CursorName> (string, read-only)
Not supported by the driver. See the note about B<Cursors> elsewhere in this
document.
=item B<Statement> (string, read-only)
Supported by the driver as proposed by DBI.
=item B<RowCache> (integer, read-only)
Not supported by the driver.
=item B<pg_size> (array-ref, read-only)
PostgreSQL specific attribute. It returns a reference to an array of integer
values for each column. The integer shows the size of the column in
bytes. Variable length columns are indicated by -1.
=item B<pg_type> (hash-ref, read-only)
PostgreSQL specific attribute. It returns a reference to an array of strings
for each column. The string shows the name of the data_type.
=item B<pg_oid_status> (integer, read-only)
PostgreSQL specific attribute. It returns the OID of the last INSERT command.
=item B<pg_cmd_status> (integer, read-only)
PostgreSQL specific attribute. It returns the type of the last
command. Possible types are: INSERT, DELETE, UPDATE, SELECT.
=back
=head1 FURTHER INFORMATION
=head2 Transactions
The transaction behavior is now controlled with the attribute AutoCommit. For
a complete definition of AutoCommit please refer to the DBI documentation.
According to the DBI specification the default for AutoCommit is TRUE. In this
mode, any change to the database becomes valid immediately. Any 'begin',
'commit' or 'rollback' statement will be rejected.
If AutoCommit is switched-off, immediately a transaction will be started by
issuing a 'begin' statement. Any 'commit' or 'rollback' will start a new
transaction. A disconnect will issue a 'rollback' statement.
=head2 Large Objects
The driver supports all large-objects related functions provided by libpq via
the func-interface. Please note, that starting with PostgreSQL 6.5 any access
to a large object - even read-only - has to be put into a transaction!
=head2 Cursors
Although PostgreSQL has a cursor concept, it has not been used in the current
implementation. Cursors in PostgreSQL can only be used inside a transaction
block. Because only one transaction block at a time is allowed, this would
have implied the restriction, not to use any nested SELECT statements. Hence
the execute method fetches all data at once into data structures located in
the frontend application. This has to be considered when selecting large
amounts of data!
=head2 Data-Type bool
The current implementation of PostgreSQL returns 't' for true and 'f' for
false. From the Perl point of view a rather unfortunate choice. The DBD::Pg
module translates the result for the data-type bool in a perl-ish like manner:
'f' -> '0' and 't' -> '1'. This way the application does not have to check the
database-specific returned values for the data-type bool, because Perl treats
'0' as false and '1' as true.
Boolean values can be passed to PostgreSQL as TRUE, 't', 'true', 'y', 'yes' or
'1' for true and FALSE, 'f', 'false', 'n', 'no' or '0' for false.
=head2 Schema support
PostgreSQL version 7.3 introduced schema support. Note that the PostgreSQL
schema concept may differ to that of other databases. Please refer to the
PostgreSQL documentation for more details.
Currently DBD::Pg does not provide explicit support for PostgreSQL schemas.
However, schema functionality may be used without any restrictions by
explicitly addressing schema objects, e.g.
my $res = $dbh->selectall_arrayref("SELECT * FROM my_schema.my_table");
or by manipulating the schema search path with SET search_path, e.g.
$dbh->do("SET search_path TO my_schema, public");
=head1 SEE ALSO
L<DBI>
=head1 AUTHORS
DBI and DBD-Oracle by Tim Bunce (Tim.Bunce@ig.co.uk)
DBD-Pg by Edmund Mergl (E.Mergl@bawue.de) and Jeffrey W. Baker
(jwbaker@acm.org). By David Wheeler <david@wheeler.net>, Jason
Stewart <jason@openinformatics.com> and Bruce Momjian
<pgman@candle.pha.pa.us> and others after v1.13.
Major parts of this package have been copied from DBI and DBD-Oracle.
B<Mailing List>
The current maintainers may be reached through the 'dbdpg-general' mailing list:
http://gborg.postgresql.org/mailman/listinfo/dbdpg-general
This list is available through Gmane (http://www.gmane.org) as a newsgroup with the name:
C<gmane.comp.db.postgresql.dbdpg>
=head1 COPYRIGHT
The DBD::Pg module is free software. You may distribute under the terms of
either the GNU General Public License or the Artistic License, as specified in
the Perl README file.
=head1 ACKNOWLEDGMENTS
See also B<DBI/ACKNOWLEDGMENTS>.
=cut